Here Ketu is considered very good. It gives wealth. This house is affected by Jupiter and Saturn. If Ketu is benefic here and Saturn is in 3rd house, it gives enormous wealth. The wealth earned by the native is more than his paternal wealth, but one tends to worry about his future. If Mercury is in 3rd it leads to Raj Yoga.
If Ketu is malefic here then the native has problem in his abdomen. The more he worries about future, more troubled he is. grandmother or mother of the native suffers, if Saturn is also malefic. Then there would be no benefit from son or house.
1. Keep black dog. 2. Wear an onyx or emerald.